The present invention relates to remote detectors and more particularly to remote troop movement detectors which are both responsive to acoustic and seismic noise.
In military operations, and in particular in military operations where the movement of the enemy on the ground cannot be directly ascertained, the requirement for a remote detector of personnel is well-recognized and many such detector configurations have been developed in the prior art. Generally such detectors where either of the acoustic or the seismic type responsive to either the acoustic noise associated with the movement of personnel and vehicles or seismic noise generated by land vehicles. For such applications the characteristic attenuation of the noise associated with troop movement, the typical background noise of the environment and power limitations dictate a detector configuration which is not easily discovered such that detection can be made before the detector is observed. Along the same requirements it is generally desired that the positioning of the sensor or its deployment do not themselves present large signatures which would cause the enemy personnel to identify and avoid the location. Accordingly there is a great necessity for detector configurations which can be configured for airdrop and are at the same time of sufficiently small dimensions to be easily carried by ground patrols. Furthermore in order to reduce logistics a common detector configuration is desired for many environments including deployment detection of enemy personnel moving through water. Many of the prior art devices are adapted for a particular environment and broader requirements usually are accompanied by larger configurations. Such highly specialized configurations require large logistic support being at the same time cumbersome and inflexible for various deployment situations.